Eibar pushed Madrid back in the first half but were made to pay for a mistake on the half-hour when Luka Modric set up Ronaldo to open the scoring.
Ronaldo scored his 17th and 18th LaLiga goals of the season to ensure victory for Los Blancos at Eibar, but only four of the strikes came before the turn of the year.
But he was back on the pitch to see Cristiano Ronaldo score his second goal of the game with what turned out to be the victor.
His double means Ronaldo has now scored in seven consecutive games and has a remarkable 13 goals overall in that period.
The home side levelled through Ivan Ramis five minutes after the break and there were chances at both ends before Ronaldo bulleted home a header five minutes from time.
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However, when his French manager was asked about his player's absence following Cristiano Ronaldo's late victor, the former midfielder was only too happy to explain the somewhat vomiting-inducing reason behind it.
Ramos nodded the ball into the bottom corner after meeting Pedro Leon's corner.
Zinedine Zidane's side was under some real pressure though, and Keilor Navas was forced to tip a curling Kike from 20 yards wide of his post.
Ronaldo should have restored the advantage but failed to convert an excellent Bale cross and from the resulting corner, Bale flashed a glancing header just wide of the post.
Lucas Vazquez and Karim Benzema replaced Isco and Toni Kroos as Zidane looked to raise the tempo and find a second goal.
But a defensive error allowed Dani Carvajal to cross and Ronaldo headed in.